JPH04252552A - Communication equipment - Google Patents

Abstract

PURPOSE:To attain sure remote communication in the communication equipment implementing remote communication according to a remote command from other communication equipment by using one line selectively with other communication equipment (e.g. telephone set). CONSTITUTION:When interruption of a current of a DC loop formed by a telephone set and a line is detected by a current sensor 2, a relay 1 is thrown from the position (a) to (b) and a relay 5 is thrown from a position (d) to (c). When a specific DTMF signal from a telephone set is received via a transformer 8 and a terminal A, the facsimile reception is transferred.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a communication device that shares one line with another communication device and performs communication operations in accordance with remote instructions from the other communication device.

0002

2. Description of the Related Art Conventionally, as an example of this type of device, a facsimile device is known which shares one telephone line with a telephone and performs facsimile communication in accordance with remote instructions from the telephone. Such a facsimile device is installed at a remote location from a telephone connected via a network control unit (NCU). When the user answers a ringing signal (incoming call) from the line using the telephone and the other party is a facsimile, the user operates the telephone's hook or numeric keypad for dialing to connect the line from the telephone to the facsimile. to perform facsimile reception (remote reception).

[0003]The N of the above-mentioned facsimile machine
The CU is configured as shown in FIG.

In the figure, terminals L1 and L2 are connected to a line N, and terminals T1 and T2 are connected to a telephone set. When a user picks up the telephone in response to a ringing signal from the line and the other party is a facsimile, the user operates the telephone to dial a predetermined number in order to receive the facsimile remotely (outputs a DTMF signal)DTM
The F signal goes from the T1 and T2 terminals to the terminal A via the transformer 8.
appears in A DTMF receiver is connected to terminal A, and the control unit recognizes the number output from the telephone from the output of the DTMF receiver, and if it is a remote reception number, it is CML.
Communication is performed by switching relay 1 to side b. Remote reception was achieved as described above.

[0005]

[Problems to be Solved by the Invention] However, in the above-mentioned conventional example, when the user
There was a problem in that the DTMF detector operated in response to the mixing of TMF signals and switched the CML relay during a call, resulting in the call being disconnected.

[0006] There is a problem in that if a number for remote reception is included in the number the user calls, the CML relay is switched and the call cannot be made. To solve this problem, it was devised to limit remote reception to a certain period of time after receiving a call, but it was not possible to start polling by remote control, and it also caused malfunctions due to interference from other lines (crosstalk). However, it was not complete.

[0007]

[Means and operations for solving the problems] In the present invention, the state of formation of a current loop between a line and another communication device (for example, a telephone) is detected by a detection means, and the line connection means is operated based on the detection result. By disconnecting the other communication device from the line and allowing the receiving means to receive a remote instruction signal from the other communication device, reliable remote communication can be performed.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be explained in detail below based on embodiments shown in the drawings.

FIG. 1 shows the configuration of a facsimile apparatus embodying the present invention. In the figure, the reference numeral 101 is a control unit composed of a microprocessor, etc., including a CPU (central processing unit) 113, a ROM (read only memory) 114, and a RAM (random access memory) 1.
15, a buffer memory 112, a line memory 110, and an encoding/decoding section 111, and controls the entire image input/output and communication processing. The ROM 114 stores a control program to be described later, and the RAM 115 is used as a work area for the CPU 113.

[0010] Image input/output is performed by a reading section 100 and a recording section 10.
2.

[0011] That is, reading the original image data is as follows:
This is performed by a reading unit 100 that includes a CCD (charge storage device) sensor, a document conveyance system, and the like. Further, received image data or image data read by the reading section 100 during a copying operation is recorded by a recording section 102 comprising a thermal printer, an inkjet printer, or the like.

Image data is input and output between the reading section 100, the recording section 102, and the encoding/decoding section 111 via a line memory 110 in units of one line. Further, data input/output between the encoding/decoding unit 111 and the communication circuit is controlled via a buffer memory 112 having a processing unit larger than one line (for example, a predetermined number of pages). Note that the encoding/decoding unit 111 performs encoding/decoding processing to suppress redundancy, and may be configured from software of the CPU 113.

Connection to a central line N such as a telephone line and data input/output are performed by a modem 106 and an NCU (network control unit) 107. A telephone or answering machine 16 for telephone calls and manual control is connected to the NCU 107 .

The operation panel 103 includes a numeric keypad for inputting a telephone number, various function keys, and the like. The operation panel 103 is provided with a display 104 used to display a telephone number, time, etc.

FIG. 2 is a diagram showing the NCU of this embodiment. 1 is a CML relay. 2 is a current sensor, which consists of a coil and a Hall element installed near the coil and insulated from the coil.The coil generates a magnetic field with a strength proportional to the current flowing through the coil, and the Hall element absorbs the magnetic field. By converting the current into a current proportional to the strength of the magnetic field,
An output current proportional to the coil current can be obtained. The output of the current sensor 2 is input to the comparator 3 and becomes a DCDET signal indicating the presence or absence of current. The DCDET signal is the control unit 1
Output to 01.

7 is a power supply for applying direct current to the telephone;
6 is a constant current circuit for increasing the alternating current impedance of the power source 7; 5 is a relay for connecting the telephone to a line or a direct current applying circuit; and 8 is a transformer.

Next, the operation of remote reception in the above configuration will be explained using FIG. 3. FIG. 3 shows the control unit 101
(or the CPU 113), and the procedures in the figure are stored in the ROM 114.

In FIG. 3, when the telephone is off-hook by the DCDET signal, the control section 101 advances the control to step S1. At this time, the state of each relay is as shown in FIG. Therefore, the DTMF receiver is disconnected from the line at the C side terminal of the relay 5, and does not remotely receive the DTMF signal generated from the telephone for making a call. In step S1, the DTDET signal is further monitored for 0.5 seconds or more.
When no current is detected for about 1.5 seconds, it is assumed that there is a hook and the process proceeds to step S2. If there is no hooking, step S1 is looped. When the relay 5 is switched to the b side in step S2, a DC current flows from the DC power supply 7 to the telephone 16 through the constant current circuit 6. Then, proceeding to step S3, the control section monitors the output of the DTMF receiver 117,
Checking whether DTMF "5" is dialed. At this time, the telephone and DTMF receiver are connected,
Since the line is disconnected at the d side terminal of relay 5, there is no need to worry about malfunctions due to crosstalk.When a user dials "5" from a telephone, "5" of the DTMF signal is T1,
The signal appears from the T2 terminal through the C side contact of the relay 5, the capacitor 9, and the transformer 8 to the A terminal of the NCU, is input to the DTMF receiver, and when the control section recognizes this, it proceeds to receive and remote reception is performed. Therefore, remote reception can be performed both when making a call and when receiving a call, and there is no fear of malfunctions due to crosstalk.

[0019] The remote reception has been explained above.
Other remote controls Other functions of the facsimile machine, such as remotely outputting a communication management report and transmitting images stored in memory to another facsimile, can also be controlled remotely.

In the above-described embodiment, a facsimile device that performs facsimile communication in response to a remote instruction from a telephone has been described, but it is not limited to a telephone that sends a remote instruction. Furthermore, the remote controlled communication device is not limited to facsimile devices, but can be applied to various communication devices such as teletexts.

[0021]

As described above, according to the present invention, a communication device capable of reliable remote communication can be provided.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing the configuration of a facsimile apparatus according to the present embodiment.

FIG. 2 is a circuit diagram of a network control unit of this embodiment.

FIG. 3 is a flowchart showing the control operation of this embodiment.

FIG. 4 is a circuit diagram of a conventional network control unit.

[Explanation of symbols]

1 CML relay 2 Current sensor 3 Amplifier 4 Hybrid transformer 5 Relay 6 Constant current circuit 7 Power supply 8　Trans 9 Capacitor 100 Reading section 101 Control section 102 Recording Department 103 Operation panel 104 Display section 105 106 Modem 107 NCU 110 Line memory 111 Encoding/decoding section 112　Buffer Memory 113 CPU 114 ROM 115 RAM 117 DTMF receiver

Claims (2)

[Claims] [Claim 1] Sharing one line with other communication devices,
In a communication device that performs a communication operation according to a remote instruction from the other communication device, a communication means for performing communication, and a line connection means for selectively connecting the line to the other communication device and the communication means. and means for receiving a remote instruction signal from the other communication device; and means for detecting the formation state of a current loop between the other communication device and the line, and A communication device characterized by disconnecting another communication device from the line and receiving a remote instruction signal from the other communication device. 2. The remote instruction signal is a specific DT.
2. The communication device according to claim 1, wherein the communication device is an MF signal.